here is my first attempt to do C programming homework and it end up pretty well..
#include <stdio.h>
#include <string.h>
main()
{
char str[100], rstr[100];
int i,k;
printf("Enter the string to reverse: ");
gets(str);
for (i=strlen(str)-1,k=0; i>=0; i--,k++)
{
rstr[k]=str[i];
}
rstr[k]='\0';
printf("string '%s' reverse '%s'\n",str,rstr);
getch();
}